CHENGDU, China -- Heather O'Reilly's goal in the 69th minute lifted the United States to a 2-2 draw with North Korea in Tuesday's Group B opening game at the Women's World Cup. The Koreans scored twice while the U.S. was a player short on the field for several minutes in the second half, before O'Reilly tied the score with a shot from about 33 feet out into the top corner of the net. The United States extended its unbeaten streak to 47 games spanning 2½ years under coach Greg Ryan. Played before 35,000 at Chengdu Sports Center Stadium, the game between the top-ranked Americans and fifth-ranked North Korea, Asia's best team and the quickest in the 16-team World Cup field, lived up to expectations. Abby Wambach gave the U.S. a 1-0 lead in the 50th minute with a long-range shot that goalkeeper Jon Myong-hui got her gloves to but was only able to deflect into the net. Minutes later, Wambach knocked heads with a teammate in a scramble around goal and exited the field with blood pouring from her face, leaving the Americans with 10 players. North Korea scored twice in her absence. Kil Son-hui benefited from a goalkeeping error, as Hope Solo let a long shot slip through her hands in the wet conditions in the 58th minute. In the 62nd, Kim Yong-ae pouncing on a rebound and shot it past Solo, who anticipated a shot to the other side of the net. Wambach came back on in the 65th minute, and her return seemed to calm things for the Americans. O'Reilly scored minutes later with a clever shot using the outside of her boot. Group B is the toughest in the World Cup with world No. 3 Sweden and African champions Nigeria also playing for a spot in the quarterfinals. The Americans face Sweden on Friday and North Korea plays Nigeria. Despite its poise, the U.S. looked unnerved at times. North Korea pressed the Americans in the first half like few teams have. Keeping the ball on the slick turf, Ri Kum-suk lashed several shots just wide of Solo. Kim Yong-ae and Kim Kyong-hwa joined Ri, putting a half dozen more shot on goal that Hope had to save. North Korea always counterattacked, seldom waiting for a slow buildup. The Americans had trouble keeping possession, but still managed threats in spurts. They looked dangerous on several corners and free kicks. In open play, Lori Chalupny and Heather O'Reilly tested Jon twice, and long crosses in from Cat Whitehill tensed up the Korean defense. The best chance for the United States -- maybe the best for either team in the first half -- came in the 40th minute. Off a corner kick from Stephanie Lopez, Wambach's header went off the crossbar behind Jon and dropped inches in front of goal before it was cleared.